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Discussion Starter #1 (Edited)
I just adjusted the valves and now I hear a knock that seems louder than before. It seems to be coming from the left side or maybe the middle. I don't think it's normal. I put in the recommended plug but had a hotter one before. Was knocking before but now it's louder. Engine oil is about half way to full (dip stick not screwed in).

Maybe someone can give me a rough idea of what the problem might be?
 

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Discussion Starter #2 (Edited)
Great... I don't seem to be able to post videos. Can it be done on Android?

Edit: downloaded Tapatalk.
 

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Post the video to YouTube and link it here?
Grizzlies are notorious for loud valves and if they were too tight before it would sound scary to you. But if in doubt, pop it back open and check it again. Better safe than sorry.
 

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Discussion Starter #4 (Edited)

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Grand High Inquisitioner
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What does it sound like when you put the stator cover plate back on tight, and the side plastic?
Anyway, I'm no expert on the sounds. With luck, Dezz will be along shortly. He knows those 660s inside and out.
 

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Discussion Starter #6
Well, I don't know if it's normal for the Grizzly to have that loud ticking sound but it's definitely coming from the engine and not the stator. Thanks for the reply. I'm a LITTLE bit less worried with you saying that they're notorious for it.

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Grand High Inquisitioner
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I was just thinking the sound might change a bit with everything buttoned up. But don't take my word for it. Wait for more responses, or check the clearance again.
 

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Discussion Starter #8
I watched a video of a Grizzly with the same noise. He eventually found he had wrist pin/piston wear. Ordered a kit and replaced. Fixed problem.

Now, I realize that the knowledgeable people out there can not make a diagnosis from watching my video but can someone tell me where to start looking? I have adjusted the valves but will do it again to make sure.

I have never taken an engine apart so is it possible, in the worst case scenario, for me to do this following the service manual and some help from GC?

I'd really appreciate your input on this.

Thanks

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Properly adjusted valves will have a ticking sound from the lash gap.
The noise in the video sounds like a rod knock to me. I don't hear the ticking sound from the valves so I suggest opening the patient back up and check the valves again.
The rocker arms will be slightly loose at T.D.C. when the valves are in proper adjustment, and this is from the lash that causes the clicking sound.
 

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Discussion Starter #10
So you're saying that the valves could be adjusted wrong and I hear rod knock because of it?

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Generally valve adjustment and rod knock are two different things.
If there is play in the wrist pin I would try the straw in the spark plug hole trick.
With the piston near the top hold a straw, possibly a long wooden dowel, on top of the piston then move the crank.
You may see the crank move without feeling the piston moving by rocking the crank back and forth.

There may be another possibility that the timing chain is not in adjustment.
 

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Scorpyon..Couple questions...
Was the noise there before you adjusted the valves? Just reread got this anwser.
Why are you running with the oil so low?
 

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Discussion Starter #13
Yes, the oil is a little low and I was planning on changing it after the valve adjustment. I'll be putting in some Yamalube 5w30 and don't want to have to drain brand new oil to fix this problem. Can I add a bit of regular 10w30 engine oil just to see if it makes a difference?



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Hard to tell what the noise is. Maybe lower the idle down as slow as possible. If it is a wrist pin you should hear a double knock.
Was the valve real tight before you adjusted them?
The 10w30 would be ok to run if it has jaso ma certification. Machine that old I'd run Rotella T4 15w40 in it. Well maybe not! I see you are "up north with the igloos"
 

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Discussion Starter #15 (Edited)
The intake valves were a bit tight but the exhaust valves were really tight. A 0.1 mm feeler could barely fit. Now they are set at .15 for intake and .2 for exhaust. Haven't rechecked them yet though.

So adding regular car engine oil to top it off for a test is a no go? I guess motorcycle oil would do.

Yeah, will be plowing snow during the winter. That's why I'll be using 5w30. Up north with the igloos but more specifically, in Sherbrooke, Quebec, Canada. So not that far up north.

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It's hard to tell anything from the video.

In my opinion, you need to double check the valve clearances. Since you stated you never heard a noise until you adjusted them.
Once double checked and known proper, then reassemble everything, including plastics, and listen again.....the plastics can make it sound different.
 

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Discussion Starter #17 (Edited)
It's hard to tell anything from the video.

In my opinion, you need to double check the valve clearances. Since you stated you never heard a noise until you adjusted them.
Actually, I said the sound wasn't as loud before adjusting but was still there. Although, the sound before was with all plastic on so I now realize that it's kinda normal to hear it louder.

The sound is most noticable in idle or when RPM's are coming down to idle. You can hear it in the video.

I will readjust the valves tonight and add a bit of oil. If that doesn't make things any better, I'll do the straw test.

I'll keep you all posted on the results.

Thanks for all the feedback!

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maybe have a look again and make sure its on tdc
and re set
maybe the valve stems have worn or mushroomed if they were that tight ?
 

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When did you last service the primary clutch? It might be the source of the noise. I have seen it more than once that noise you hear in one spot is actually coming from a completely different area. Had a guy with a Grizzly 660 once that thought his transmission was coming apart with noises coming from the back of the engine. Turned out it was the rear diff coming out of the frame.

On the other hand, do you actually have a problem? Are you tracking a ghost or a problem that doesn't exist? It's hard for me to tell without actually being there.
 

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Discussion Starter #20
I personally have never serviced the clutch. I bought it just a few weeks ago. Going through all parts of the Grizzly and servicing as I go. I really hope I'm just chasing a ghost but that knocking noise is really bugging me and it really seems to be coming from the middle/left side of the engine.

I'm starting to work on it now. I had to warm up the garage first, apparently winter is coming. I'm gonna reset the valves, top up with oil and see what happens.

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